A taxonomic key of the Labrisomid fishes from Chile is presented. This taxon is conformed by Auchenionchus crinitus (Jenyns, 1842), A. microcirrhis (Valenciennes, 1836), A. variolosus (Valenciennes, 1836), Calliclinus geniguttatus (Valenciennes, 1836), C. nudiventris Cervigón & Pequeño, 1979, and Labrisomus (Labrisomus)philippii (Steindachner, 1866). This family has suffered numerous but partial taxonomic changes, making its study difficult not only because of the lack of an unifying document where all these changes are registered, but also because of the high degree of morphological similarity among their component taxa. The present key collected those modifications and comments on diverse taxonomic changes and the synonymies about these fishes, from their description until now. The diagnostic characters have been selected to facilitate the study of each species that represents this taxon, allowing an accurate and fast diagnosis in Chilean labrisomid fishes.